Tool-grinder.



PATENTED AUG. 18, 1903. R. U. GREBNER-D.

TOOL GRINDER. APPLICATION FILED NOV. 7, 1902.

N0 MODEL.

'NVENTOF? WITNESSES Tatented August 18, 1903.

UNITED STATES PATENT OFFICE.

ROBERT C. GREENERD, OF WINTHROP, MASSACHUSETTS.

TOOL-GRINDER.

SPECIFICATION forming part of Letters Patent No. 736,843, dated August18, 1903.

Application filed November 7,1902. Serial No. 130,891. No model.)

To all whom it may concern:

. Be it known that 1, ROBERT C. GREENERD, a citizen of the UnitedStates, residing at Winthrop, in the county of Suifolk and State ofMassaehusetts,have invented certain new and useful Improvements inTool-Grinders; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

This invention relates to machines for grinding tools, especially tothose machines in which rotating grindingwheels are used and in whichmeans are provided for holding in the proper position the tool to beground.

This invention has among other objects the following: to provide for theequal distribution of Wear over the Working surface of thegrinding-wheel, to provide improved means for rapidly adjusting theposition of the tool with respect to the grinding-surface whereby thecorrect angle may be imparted to the cutting portion of the tool, toprovide means whereby the ground surface of the tool may be madeconcave, and to reorganize and improve machines of this character inother respects hereinafter pointed out.

The present invention consists in the devices and combinations ofdevices hereinafter described and claimed.

In the drawings accompanying this specification, Figure 1 is a frontelevation of a machine embodying my invention, the lower part of themachine being broken away. Fig. 2 is a side elevation looking toward theleft of Fig- 1. Fig. 3 is avertical section of the tool-rest. Fig. 4 isa front view of the tool-rest.

The illustrated embodiment of my invention is constructed as follows:

To the column or standard 1 of an ordinary grinding-machine is attacheda base-plate 2, which carries all the mechanisms peculiar to thisinvention. The grinding-wheel 3 has its working face upon an annularraised portion on its side-21 9., it'is known by those skilled in theart as a side-grinding wheel. The wheel is carried on a spindle inbearingst f on the column 1. A belt 5 around a pulley on a counter shaftin the base of the machine {not shown) drives the spindle and the wheel.

The tool-carriage is made as follows: Upon a plate 6 is a lug 7 to whichis bolted a lug on a tool-clamp 8. This clamp is adapted to hold theshank of a tool to be ground by means of a set-screw 9, and the jointdescribed permits the angle of presentation of the tool to the face ofthe wheel to be conveniently adjusted. A second clamp 10 is rigidlyfixed to the plate, at an angle of ninety degrees to the surfacethereof,andathird clampllis attached at an angle of sixty degrees. Atable 12, attached perpendicularly to the face of the plate, has groovesupon its face of a width sufficient to receive the shank of a tool.These grooves are arranged, preferably, at an angle of sixty degreeswith one another. By resting a tool in these grooves successively andpresenting the end of the tool to the Wheel, steadying the tool by hand,an angle of sixty degrees may be quickly and conveniently imparted tothe point of the tool, as is desirable in the case of a thread-tool. Theportion of the tool-carriage as thus far described constitutes a toolrest or support. The plate 6 has a stem 13, which may be rotated andclamped in a split sleeve 14. By means of a spring-pressed pincooperating with holes in the plate the latter may be conveniently setat predetermined angles. This sleeve 14 has also a stem embraced by thesplit sleeve 15, in which it may be swiveled and clamped. The sleeve 15is attached to the end of a feed-slide 16, which is carried in ways 17and moved by a pinion on the shaft of a hand-wheel 18, the said pinionmeshing with a rack on the bottom of the slide. The ways are pivoted toan arm 19, the other end of which is pivoted to a vertical stem 20,which may be rotated, raised or lowered, and clamped in a split sleeve21.

By means of the above-described arrangements tools of various forms maybe rapidly and conveniently ground to the correct angle. In grinding athread-tool for a lathe the rest is rotated about its stem 13 until thegrooved table 12 is in ahorizontal position. The rest is clamped in thisposition by the split sleeve 14. The upper part of the carriage is thentilted about its joint upon the upper end of the arm 19 in order to givethe proper clearance to the point of the tool. The entire carriage isthen lowered by loosening the split sleeve 21 and lowering the stemtherein in order to bring the end of the tool opposite the proper partof the grinding-wheel. The tool to be ground is then held in the twogrooves in the table successively by hand and the rest moved forwardbythe hand-wheel 18 in order to bring the tool in contact with thegrinding-wheel.

'In this wa T an an le of sixt Y de rees is imparted to the point of thetool without any further adjustment. To grind a diamond-point tool, thetool is clamped in the swivel-clamp 8, which is then rotated to theposition now occupied in the drawings by the grooved table, and theclamp is turned about its joint upon the lug 7 to give the correct angleto the end of the tool. After grinding one side of the tool with theclamp in this position the clamp is turned in the opposite directionupon its swivel in order to grind the other side of the tool. The top ofthe point is then ground by turning the rest around the axis of the stem15 and rotating it through an angle of ninety degrees about the stem 13.A side tool is held in the adjustable clamp or any of the fixed clamps,and to grind the side of the tool the carriage is rotated about the stem15 through an angle of about ninety degrees from the position shown inthe drawings. In order to grind the top of the tool, the rest is thenrotated through a sufficient angle about the stem 13.

In order that the wear may be equally distributed over the face of thewheel, means are provided for giving to the tool a reciprocating motionsubstantially parallel to an element of the grinding-surface. The sleeve21 is attached to a horizontal stem 22, which is free to turn in asleeve 23. This sleeve is adjustably attached to the base-plate by astem 24, clamped in a lug 25, extending from the baseplate. An arm 26,attached to the sleeve 21, is connected by a universal joint to aconnecting-rod 27, the other end of which is connected by a universaljoint to a stud 28, free to turn in a journal in a worm-wheel29.Thewormwheel turns on a stud fixed to an extension from the bed-plate.The worm-wheel is rotated bya worm 30, fixed to a shaft 31, on the otherend of which is fixed a pulley 32, over which the belt 5 passes. Thepitch of the worm is such that it communicates a slow revolution to theworm-wheel, and as the axis of the latter is above the path of motion ofthe end of the arm 26 a reciprocating motion is communicated to the armby the connectingrod. In this manner the entire tool-rest is oscillatedabout the axis of the stem 22 and sleeve 23, and the tool, remainingconstantly in contact with the face of the wheel, is caused to traversethe face, so that the form of the wheel is perfectly preserved and it isimpossible for grooving to occur. To provide for lateral adjustment ofthe tool across the face of the wheel, the connecting-rod 27 is dividedand the ends threaded left and right and a turnbuckle or nut 33 isprovided by means of which the length of the connecting-rod may bevaried and the angular position of the carriage altered.

As those skilled in the art are aware, a tool will out better if theground surfaces are slightly concave. In my machine I make the workingface of the wheel in the form of a truncated cone, which permits thegrinding of concave surfaces. In order that the conical surface of thewheel may be preserved, the path of oscillation of the tool should besubstantially parallel to an element of the conicaldicular to the faceof the wheel- In this position it would be properly arranged for the useof a wheel with a fiat face, as shown by dotted lines, Fig. 2.

I am aware that it has been proposed in the prior art to reciprocate atool being ground over the grindingsurface of the grindingwheel in thedirection of motion of the surface of the grinding-wheel; but such aconstruction is clearly differentiated from my invention in importantrespects and among others by the fact that in my construction the toolis reciprocated across the face of the grindingwheel and in a lineperpendicular to the direction of motion of the surface of thegrinding-wheel in contact with the tool.

I am also aware that it has been proposed in the prior art toreciprocate a tool being ground across the face of a grinding-wheel oncefor each revolution of the wheel; but such construction is clearlydifferentiated from my invention by the fact that certain portions ofthe grinding-wheel are never brought in contact with the tool, While inmy machine every portion of the grinding-surface of the grinding-wheelis brought in contact with the tool with as much fre qu ency as everyother portion.

Wherever in the claims I have used the term tool-holder I intend therebyto include any sort of means forholding the tool to be ground.

The present invention is not limited to the specific embodiment thereofillustrated in the drawings and described herein, as it may be embodiedin otherforms widely differingtherefrom in construction whicharewithinthespirit of my invention.

Having thus described my invention, I de sire to secure by LettersPatent- 1. A tool-grinder, having, in combination, a rapidly-rotatinggrinding-wheel, means for holding a tool in contact with the grindingsurface of the grinding-wheel, and automatic means for imparting a slowrelative motion to the grinding-wheel and tool-holder so as to move thetool transversely to the direction of motion of the portion of thesurface of the grinding-wheel in contact therewith continuously duringthe grinding operation, so that upon each successive rotation of thewheel the tool will come in contact with different portions of thegrinding-surface of the wheel, substantially as described.

2. A tool-grinder, having, in combination,

a rapidly-rotating grinding-wheel provided with a grinding-surface onits side, a toolholder for supporting a tool in position to be actedupon by the grinding-surface of the 3. A tool-grinder, having, incombination,

a rapidly-rotated grindingwheel, and means for holding a tool in contactwith the grind ing-surface of the grinding-wheel, one of said membersbeing held in fixed position and the other of said members beingsupported to oscillate in a plane parallel to the grinding-sur face ofthe grinding-wheel and in a line substantially normal to the directionof motion of such grinding-surface at the point of contact, andautomatic means for imparting a slow relative motion to thegrinding-wheel and tool-holder, substantially as described.

4. A tool-grinder, having, in combination, a grinding-wheehanoscillating tool-holder,

means for oscillating the tool-holder consisting of a rotating memberhaving an eccentric stud secured thereto, and connections between saideccentric stud and the oscillating toolholder, substantially asdescribed.

4 5. A tool-grinder, having, in combination, a grinding-wheel and atool-rest, said rest comprising a plurality of clamps adapted to holdthe tool to be ground, said clamps being fixed at different angles withthe axis of the toolrest, substantially as described.

6. A tool-grinder, having, in combination, a grinding-wheel, anoscillatory tool-holder, means for actuating the tool-holder comprisinga pulley adapted to engage the belt by which the grinding-wheel isdriven, substantially as described.

7. A tool-grinder, having, in combination, a grinding-wheel, atool-holder, a feed-slide, said tool-holder and feed -slide beingconnected by universal adjusting means, an arm to the upper end of whichthe feed-slide is pivotally connected, a stem to the upper end of whichthe lower end of the arm is pivotally connected, a clamp-sleeve forembracing the stem, and means for pivotally supporting the said sleeve,substantially as described;

8. A tool-grinder, having, in combination, a rapidly-rotatinggrinding-wheel, means for holding a tool in contact with thegrindingsurface of the grinding-wheel, means for oscillating one or saidmembers in a plane parallel to the grinding surface of the grindingwheel and in a line substantially normal to the direction of suchgrinding-surface at the point of contact, and means for adjusting theaxis of oscillation of said oscillating means, substantially asdescribed.

In testimony whereof I affix my signature in presence of two witnesses.

ROBERT C. GREENERD. Witnesses:

HoRAcE VAN EVEREN, FARNUM F. DORSEY.

